When you swallow, the muscles of your esophagus contract and push food and liquids toward your stomach. Sphincters (rings of muscle) inside the esophagus open to let food and liquid through, then close to keep food, liquids, and stomach acid from moving backward up into the esophagus. The sphincter at the top of the esophagus is called the upper esophageal sphincter (UES), and the sphincter at the bottom of the esophagus is called the lower esophageal sphincter (LES).
Manometry is performed to see if the esophagus is contracting properly.
Sources:
"American Gastroenterological Association medical Position Statement: Clinical Use of Esophageal Manometry." National Guideline Clearinghouse Date Modified: 3/9/2009 18 Mar 2009
Michael F. Vaezi, M.D., Ph.D., and Joel E. Richter, M.D., "Diagnosis and Management of Achalasia." The American College of Gastroenterology 18 Mar 2009
